![]() Experimental approach of anti-predator behaviours in the Nile Tilapia (Oreochromis niloticus L.) : detection and evaluation of predation risk by juvenile fish.Delcourt, Johann ; Poncin, Pascal ![]() Poster (2003) Detailed reference viewed: 2 (1 ULg)![]() Experimental approach of the behavioural spawning tactics in Barbus meridionalis using paternity analysis.; Poncin, Pascal ; et alPoster (1997) Detailed reference viewed: 4 (0 ULg) An Experimental Approach to Link Powder Physical Properties to 3D Particle ShapeCalifice, Arnaud ; Lumay, Geoffroy ; Vandewalle, Nicolas et alin Particulate Systems Analysis 2011 (2011, September) A series of samples have been characterized by 3D image analysis (using X-Ray microtomography). The samples consist of blends of metallic particles: steel shot abrasives (“balls”), steel fibres and ... [more ▼] A series of samples have been characterized by 3D image analysis (using X-Ray microtomography). The samples consist of blends of metallic particles: steel shot abrasives (“balls”), steel fibres and angular steel grit particles. The blends were systematically prepared in different proportions of the raw products. Various shape and size parameters were measured on the particles: equivalent volume diameter (dV), maximum inscribed sphere diameter (dIN), particle length (maximum Feret diameter), particle elongation (El), particle flatness (Fl) etc. The results are expressed as statistical shape and size parameters, expressed both as volume and number weighted distributions. The blends have been tested for compaction using a cylindrical container which experiences a series of 500 free falls over a height of 3mm. The compaction dynamics was monitored using a sensor that measures the evolution of the solid volume fraction as a function of the tap number. From the obtained compaction curve, the Hausner ratio and a flowability index were extracted. The same blends have also been analysed using a rotating drum at different rotation speeds to analyze the evolution of the flowing angle. As the system is based on the analysis of a time sequence of 50 images (separated by 0.5 sec) it is possible to measure the intermittent character of the powder flow. The resulting measure is a cohesive index of the powder. The results obtained from physical testing were systematically plotted as a function of various statistical indices of the shape and size distributions in order to reveal correlations between particle shape properties and physical behaviour. Some clear trends appeared, demonstrating the influence of particle shape on powder physical properties. [less ▲] Detailed reference viewed: 38 (6 ULg) EXPERIMENTAL CHALLENGES TO THE STANDARD MODEL: A REEVALUATIONCudell, Jean-René ![]() Doctoral thesis (1987) Detailed reference viewed: 8 (4 ULg) Experimental characterisation and modelling of homogeneous solid suspension in an industrial stirred tankCalvo, Sébastien ; Delafosse, Angélique ; Collignon, Marie-Laure et alin Advances in Mechanical Engineering (2013), Volume 2013 In this work, we study the conditions needed to reach homogeneous distribution of aluminium salts particles in water inside a torispherical bottom shaped stirred tank of 70 L equipped with a Pfaudler RCI ... [more ▼] In this work, we study the conditions needed to reach homogeneous distribution of aluminium salts particles in water inside a torispherical bottom shaped stirred tank of 70 L equipped with a Pfaudler RCI type impeller and three equispaced vertical baffles. The aim of the present study is to develop a CFD model describing the quality of particle distribution in industrial scale tanks. This model, validated with experimental data, is used afterwards to develop scale-up and scale-down correlations to predict the minimum impeller speed needed to reach homogeneous solid distribution Nhs.The commercial CFD software Fluent 14 is used to model the fluid flow and the solid particle distribution in the tank. Sliding Mesh approach is used to take the impeller motion into account. Assuming that the discrete solid phase has no influence on the continuous liquid phase behaviour, the fluid flow dynamics is simulated independently using the well-known k-ε turbulence model. The liquid-solid mixture behaviour is then described by implementing the Eulerian Mixture model. Computed liquid velocity fields are validated by comparison with PIV measurements. ComputedNhs were found to be in good agreement with experimental measurements. Results fromdifferent scales allowed correlating Nhs values to the volumetric power consumption. [less ▲] Detailed reference viewed: 8 (5 ULg) Experimental Characterisation of Damage Occuring during Single Point Incremental Forming of a Ferritic SteelMertens, Anne ; Guzmán Inostroza, Carlos Felipe ; Habraken, Anne et alPoster (2012, September) Single Point Incremental Forming (SPIF) has been developed as a new dieless process for forming metal sheets. This technique appears very promising in view of the current requirements for rapid ... [more ▼] Single Point Incremental Forming (SPIF) has been developed as a new dieless process for forming metal sheets. This technique appears very promising in view of the current requirements for rapid prototyping and/or small series production [1]. However, inaccuracies in the shape of the processed part and material failure constitute important limiting factors for applications. In the present research, a numerical approach, based on the damage model proposed by Gurson [2], has been chosen to analyse and optimise the process, predict the material rupture and the process limit. From experimental observations of plastic deformation and ductile fracture, damage is related to the nucleation, growth and coalescence of microvoids [3]. Gurson’s model uses the volume fraction of these voids as a main variable. Hence the determination of this value is a key factor for a correct identification and validation of the model. More particularly, the present work focuses on two different methods used to experimentally characterise damage occurring during single point incremental forming of a ferritic steel. Void measurements carried out by optical microscopy combined with image analysis have been compared with porosity values obtained from density measurements based on the Archimedes’ principle [4], so as to assess the feasibility of using this method for a quick characterisation of the damage. [less ▲] Detailed reference viewed: 66 (30 ULg) Experimental characterization and constitutive modeling of TA6V mechanical behavior in plane strain state at room temperatureGilles, Gaëtan ; Tuninetti Vásquez, Victor ; Ben Bettaieb, Mohamed et alin AIP Conference Proceedings (2011), 1383 This paper presents an experimental and theoretical study of the quasi-static behavior of TA6V titanium alloy in plane strain state. In order to quantify the anisotropy of the material, tests were carried ... [more ▼] This paper presents an experimental and theoretical study of the quasi-static behavior of TA6V titanium alloy in plane strain state. In order to quantify the anisotropy of the material, tests were carried out at room temperature on specimens cut out from a sheet along three loading directions. The initial yield locus is described by the phenomenological CPB06ex3 criterion and Voce’s type isotropic hardening is used. Finite element simulations are performed and compared with the experiments. [less ▲] Detailed reference viewed: 41 (27 ULg) Experimental characterization and constitutive modeling of TA6V titanium mechanical behavior in tension and compressionGilles, Gaëtan ; Hammami, Walid ; Libertiaux, Vincent et alConference (2010) Detailed reference viewed: 54 (29 ULg) Experimental characterization and elasto-plastic modeling of the quasi-static mechanical response of TA-6 V at room temperatureGilles, Gaëtan ; Hammami, Walid ; Libertiaux, Vincent et alin International Journal of Solids & Structures (2011), 48(9), 12771289 The paper presents an experimental study of the quasi-static deformation behavior of a TA-6V in sheet form. To quantify the plastic anisotropy and the tension-compression asymmetry of this material at ... [more ▼] The paper presents an experimental study of the quasi-static deformation behavior of a TA-6V in sheet form. To quantify the plastic anisotropy and the tension-compression asymmetry of this material at room temperature, monotonic tensile and compressive tests were carried out on specimens cut out along several orientations in the plane of the sheet. It was observed that although the tensile flow stress anisotropy is very mild, the Lankford coefficients’ anisotropy is very pronounced. To describe the observed mechanical response an elastic/plastic approach was used. Yielding was described using a family of yield criteria that account for strength differential effects and allow an improved description of the anisotropy and its evolution through multiple linear transformations. Comparisons between uniaxial monotonic data and FE simulations using the model show a very good agreement. [less ▲] Detailed reference viewed: 67 (48 ULg) Experimental characterization of a hermetic scroll expander for use in a micro-scale Rankine cycleLemort, Vincent ; Declaye, Sébastien ; Quoilin, Sylvain ![]() in Proceedings of the Institution of Mechanical Engineers, Part A, Journal of Power and Energy (2011) This paper presents the results of an experimental study carried out on a prototype of a hermetic scroll expander, integrated into a gas cycle test rig, whose working fluid is HFC-245fa. This system was ... [more ▼] This paper presents the results of an experimental study carried out on a prototype of a hermetic scroll expander, integrated into a gas cycle test rig, whose working fluid is HFC-245fa. This system was designed to test only the performance of the expander. It is mainly made up of a scroll compressor, a scroll expander, a heat exchanger and a by-pass valve. The latter is used to adjust the pressure ratio imposed to the expander. The expander is originally a compressor designed for heat pump applications and characterized by a nominal power input of 2.5 kWe. Performance of the expander is evaluated in terms of isentropic effectiveness and filling factor as function of the main operating conditions. The study also investigates the impact of oil mass fraction on the expander performance. Maximum overall isentropic effectiveness of 71.03% is measured, which is partly explained by the good volumetric performance of the machine. Using the experimental data, parameters of a semi-empirical simulation model of the expander are identified. This model is used to analyze the measured performance of the expander. Finally, a polynomial empirical model of the expander is proposed for fast and robust simulations of ORC systems. [less ▲] Detailed reference viewed: 259 (27 ULg)![]() Experimental characterization of hafting traces and their recognition in archaeological assemblagesRots, Veerle ; in Walker, E. A.; Wenban-Smith, F.; Healy, F. (Eds.) Lithics in Action. Papers from the Conference Lithic Studies in the Year 2000 (2004) Detailed reference viewed: 7 (0 ULg) Experimental co-infections of calves with Bluetongue virus serotypes 1 and 8Dal Pozzo, Fabiana ; Martinelle, Ludovic ; Thys, Christine et alin Veterinary Microbiology (2013) Detailed reference viewed: 3 (0 ULg) Experimental comparison of cavity sealing ability of five dental adhesive systems after thermocycling; Geerts, Sabine ; Gueders, Audrey et alin Journal of Adhesive Dentistry (2003), 5(2, Summer), 139-144 Purpose: To evaluate the cavity sealing obtained after thermocycling with five adhesive systems in which one all-in-one adhesive was compared to three one-bottle adhesives, and to observe the effect of a ... [more ▼] Purpose: To evaluate the cavity sealing obtained after thermocycling with five adhesive systems in which one all-in-one adhesive was compared to three one-bottle adhesives, and to observe the effect of a low-charged resin layer added to a one-bottle adhesive. Materials and Methods: Twenty-five recently extracted teeth were randomly allocated to five experimental adhesive systems (n = 5 each): Optibond Solo (OS), Scotchbond 1 (SB1), PQ 1, Prompt-L-Pop (PLP), SB1+Revolution (R). On each tooth, two rectangular cavities at the cementoenamel junction were filled with a microhybrid composite (Z100) and the tested adhesives. Teeth were thermocycled and stained with AgNO3 + vitamin C. Leakage was evaluated on a 6-point (0-5) severity scale and the highest score was selected for each restoration. Results were treated by ordinal logistic regression and considered to be significant at p < 0.05. Results: No significant difference was found between leakage values for enamel and dentin interfaces. Leakage scores never exceeded 2 for OS, SB1 and SB1+R, while they reached a maximum of 5 in 20% of PLP cases. OS was significantly better than the other adhesive systems, which were statistically equivalent. The addition of a flowable composite layer on SB1 did not yield a significant difference, but tended to give better results mainly at the dentin interface. Conclusion: The all-in-one adhesive PLP because of quite variable results, seems less reliable than the one-bottle adhesives, of which OS provides significantly the best results. Addition of a flowable composite on SB1 appears to yield slightly better results. [less ▲] Detailed reference viewed: 43 (1 ULg)![]() Experimental constraints on the parent magma composition and density changes during crystallization of the Bjerkreim-Sokndal layered lopolith (southern Norway)Vander Auwera, Jacqueline ; in Terra Abstracts (1993), 5 Detailed reference viewed: 3 (1 ULg)![]() Experimental cross transmission of Bovine Leukemia Virus (BLV) between several animal species.; Portetelle, Daniel ; in Zentralblatt für Veterinarmedizin. Reihe B = Journal of Veterinary Medicine. Series B (1981), 28 Detailed reference viewed: 3 (0 ULg)![]() Experimental cross transmissions of Bovine Leukemia Virus (BLV) between several animal species.; Portetelle, Daniel ; in Straub, O. C. (Ed.) Current Topics in Veterinary Medicine and Animal Science (1982) Detailed reference viewed: 7 (0 ULg) Experimental demonstration of transient resonance capture in a system of two coupled oscillators with essential stiffness nonlinearityKerschen, Gaëtan ; ; et alin Journal of Sound & Vibration (2006), 299(4-5), 822-838 The purpose of this paper is to report an experimental study of transient resonance capture that may occur in a system of two coupled oscillators with essential (i.e., nonlinearizable) nonlinearity. It is ... [more ▼] The purpose of this paper is to report an experimental study of transient resonance capture that may occur in a system of two coupled oscillators with essential (i.e., nonlinearizable) nonlinearity. It is shown that during transient resonance capture the two oscillators are in a state of resonance, the frequency of which varies with time, which leads to targeted nonlinear energy transfer. Further evidence of resonance capture is a non-time-like behavior of the phase difference between the oscillators; this quantity is monitored using the Hilbert transform or the Huang Hilbert transform in the case of multifrequency response signals. (c) 2006 Elsevier Ltd. All rights reserved. [less ▲] Detailed reference viewed: 13 (1 ULg) Experimental Design applied to spin coating of 2D colloidal crystal masks : a relevant method?Colson, Pierre ; Cloots, Rudi ; Henrist, Catherine ![]() in Langmuir (2011), 27(21), 12800-12806 Monolayers of colloidal spheres are used as masks in nanosphere lithography (NSL) for the selective deposition of nanostructured layers. Several methods exist for the formation of the self-organized ... [more ▼] Monolayers of colloidal spheres are used as masks in nanosphere lithography (NSL) for the selective deposition of nanostructured layers. Several methods exist for the formation of the self-organized particles monolayers, among which spin coating appears to be very promising. However, a spin coating process is defined by several parameters like several ramps, rotation speeds and durations. All parameters influence the spreading and drying of the droplet containing the particles. Moreover, scientists are confronted to the formation of numerous defects in spin coated layers, limiting well-ordered areas to a few µm2. So far, empiricism mainly ruled the world of nanoparticles self-organization by spin coating and much of the literature is experimentally based. Therefore, the development of experimental protocols to control the ordering of particles is a major goal for further progress in NSL. We applied experimental design to spin coating, to evaluate the efficiency of this method to extract and model the relationships between the experimental parameters and the degree of ordering in the particles monolayers. A set of experiments was generated by the MODDE software and applied to the spin coating of latex suspension (diam. 490 nm). We calculated the ordering by a homemade image analysis tool. The results of Partial Least Squares (PLS) modeling show that the proposed mathematical model only fits data from strictly monolayers but is not predictive for new sets of parameters. We submitted the data to Principal Component Analysis (PCA) that was able to explain 91% of the results when based on strictly monolayers samples. PCA shows that the ordering was positively correlated to the ramp time and negatively correlated to the first rotation speed. We obtain large defect-free domains with the best set of parameters tested in this study. This protocol leads to areas of 200 µm2, which has never been reported so far. [less ▲] Detailed reference viewed: 52 (18 ULg) The experimental design as practical approach to develop and optimize a formulation of peptide-loaded liposomesDucat, Emilie ; ; Lecomte, Frédéric et alin AAPS PharmSciTech (2010), 11(2), 966-975 To investigate the encapsulation of Print 3G, a peptidic agent that could reduce the angiogenic development of breast tumors, pegylated liposomes used as intravenous vectors were studied and characterized ... [more ▼] To investigate the encapsulation of Print 3G, a peptidic agent that could reduce the angiogenic development of breast tumors, pegylated liposomes used as intravenous vectors were studied and characterized. Recently, the path of liposomes has been explored with success to improve the pharmacological properties of peptidic drugs and to stabilize them. In this study, loaded unilamellar vesicles composed of SPC:CHOL:mPEG2000-DSPE (47:47:6) were prepared by the hydration of lipid film technique. An HPLC method was developed and validated for the determination of Print 3G to calculate its encapsulation efficiency. Observed Print 3G adsorption on different materials employed during liposome preparation (such as glass beads, tubing, and connections for extrusion) led to the modification of the manufacturing method. The freeze-thawing technique was used to enhance the amount of Print 3G encapsulated into blank liposomes prepared using the hydration of lipid film procedure. Many factors may influence peptide entrapment, namely the number of freeze-thawing cycles, the lipid concentration, the peptide concentration, and the mixing time. Consequently, a design of experiments was performed to obtain the best encapsulation efficiency while minimizing the number of experiments. The lipid concentration and the number of freeze-thawing cycles were identified as the positive factors influencing the encapsulation. As a result of the optimization, an optimum was found and encapsulation efficiencies were improved from around 30% to 63%. Liposome integrity was evaluated by photon correlation spectroscopy and freeze-fracture electron microscopy to ensure that the selected formulation possesses the required properties to be a potential candidate for further in vitro and in vivo experiments. [less ▲] Detailed reference viewed: 42 (25 ULg) Experimental design for a study of drowsiness using a driving simulatorFrançois, Clémentine ; Wertz, Jérôme ; Langohr, Thomas et alPoster (2012, October 05) Detailed reference viewed: 36 (17 ULg) |
||